Comparison of two fetoscopic open neural tube defect repair techniques: single- vs three-layer closure

We reported previously on an exteriorized-uterus fetoscopic repair for open neural tube defect (ONTD) using a single-layer closure (SLC) technique. However, because SLC was associated with a high rate of cerebrospinal fluid (CSF) leakage at birth, we developed a three-layer closure (3LC) technique comprising a bovine collagen patch, a myofascial layer and a skin layer. The aims of this study were to compare SLC and 3LC in terms of intraoperative, postoperative and obstetric outcomes, as well as short-term neonatal neurologic and non-neurologic outcomes.

This was a retrospective analysis of prospectively collected data, from 32 consecutive SLC controls and 18 consecutive 3LC cases, that underwent exteriorized-uterus two-port fetoscopic repair of ONTD at our center, between April 2014 and December 2018. All patients satisfied the Management of Myelomeningocele Study (MOMS) criteria. Obstetric, maternal, fetal and early neonatal outcomes were compared between the SLC and 3LC groups.

Maternal demographics and mean gestational age (GA) at fetal surgery (25.0 ± 0.7 vs 25.0 ± 0.5 weeks' gestation; P = 0.96), and at delivery (36.5 ± 3.5 vs 37.6 ± 3.0 weeks; P = 0.14), were similar between the SLC and 3LC groups, respectively. The rate of preterm prelabor rupture of membranes (PPROM) < 37 weeks (28% vs 29%; P = 0.9), mean GA at PPROM (32.3 ± 3.4 vs 32.7 ± 1.9 weeks; P = 0.83) and rate of vaginal delivery (50% vs 47%; P = 0.84) were similar for the SLC vs 3LC groups, respectively. In pregnancies that had SLC compared with those that had 3LC, there was a significantly higher incidence of CSF leakage at birth (8/32 (25%) vs 0/17 (0%); P = 0.02) and a significantly lower rate of reversal of hindbrain herniation at 6 weeks postoperatively (18/30 (60%) vs 14/15 (93%); P = 0.02). The rate of infants that met the MOMS criteria for shunt placement or died before 12 months of age (23/31 (74%) vs 7/12 (58%); P = 0.31) and those that required treatment for hydrocephalus by 12 months (15/32 (47%) vs 4/12 (33%); P = 0.42) were similar between the SLC and 3LC groups, respectively.

Compared to SLC, 3LC preserves the fetal and obstetric benefits of fetoscopic repair and shows improved rates of CSF leakage and reversal of hindbrain herniation at 6 weeks postoperatively. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.